The arrest today of a white supremacist gang member in connection with the murder of Colorado's prisons chief has highlighted the emerging threat of these prison gangs as they spill out onto the streets.

The arrest of James Franklin Lohr, 47, comes weeks after police in Colorado said they believe Evan Ebel, 28, was involved in the murder of Tom Clements. Ebel was killed in a shootout with cops in Texas two days after the murder.

Lohr and a second man, Thomas James Guolee, 31, were wanted for questioning because they were believed to be in contact with Ebel in the days before Clements was killed, authorities said. It's not clear if Lohr has been charged with a crime. Guolee is still at large. All three are members of the white supremacist gang known as the 211 Crew, authorities said.

Police in Texas have focused on another white prison gang, the Aryan Brotherhood of Texas, as one possible culprit in the murders of two prosecutors in Kaufman County. The murders of Michael McLelland and Mark Hasse came after authorities issued a warning that the gang was planning "mass casualties" against law enforcement personnel who had help indict more than 30 gang members.

Both gangs represent a shift for white supremacist prison gangs who once operated solely behind bars to gangs that are now spilling out onto streets, running criminal enterprises outside of prison, ordering hits on individuals out in the "free world," and recruiting members who are not inmates, according to experts.

"Many of these gangs have evolved to have a substantial street presence," said Mark Pitcavage, director of investigative research for the Anti-Defamation League. "Most Americans don't realized they could be their neighbors."

Almost all prison gangs, Pitcavage said, have grown in numbers, profits, and influence by producing and trafficking meth across their regions.

The Aryan Brotherhood of Texas, which is not a part of the more widely-known Aryan Brotherhood based in California, controls meth in much of Texas, according to Pitcavage and Mark Potok, a senior fellow at the Southern Poverty Law Center, which monitors hate groups.

"Their big thing, the ABT, is that they have been running a multimillion dollar drug racket, mainly methamphetamines and heroin, and to a lesser extent cocaine and marijuana. But there's also a lot of extortion on other inmates, armed robbery, murders, attempted robberies, and so on," said Potok.

Both the ABT and the 211 Crew operate inside state prisons and on the streets, with incarcerated leaders often calling the shots from behind bars.

"What's astounding is these people are able to run criminal empires from their prison cells, even in many cases when they're being held in segregation, in solitary confinement. It's remarkable," Potok said.

"The vast majority of these leaders are in prison, serving life sentences, yet able to run criminal empires, up to and including ordering hits on people on the outside from their cells," he said.

The structure of the gang is often copied from military or law enforcement, with ranking generals at the top all the way down to soldiers and prospects at the bottom.

"Every gang has its own system," Pitcavage said. "The ABT has a paramilitary system, with generals, then majors, captains, lieutenants, and sergeants. Captains are the key lower rank, in charge of a particular prison unit or particular city or county, the local boss."

Violent White Prison Gangs in Spotlight

"We have conflicting reports about the 211 Crew," he said, noting that the ADL has information that 211 Crew may operate with a paramilitary structure, but other information that indicates "they don't have much structure at all beyond a few shot-callers."

Both gangs are incredibly violent and lethal, the experts said, with the 211 Crew particularly violent to its own members, expecting them to maintain their membership and participation even after leaving prison.

"A 211 rule is that you must stay in the gang when you leave. You are expected to earn," Potok said.

Richard Ely, an attorney who has represented Aryan Brotherhood of Texas, admitted that the ABT expects members to stay loyal, and can become violent if they are not.

"Once you're on the inside, you're never out," Ely said. "And if they kick you out, they either beat you up badly or they could kill you based on what you've done. I don't know about any sort of retirement plan. Most of the older members are retired on the Uncle Sam system, serving life sentences."

"If you break the rules, if you do something that is not in the gang's best interest, a number of brothers will grab you, take you out to the woods and beat you, to the extent you will probably need to be hospitalized," he said. "And if you take your punishment like a man you're back in."

Members of early prison gangs, from when they began in the 1960s until about the 1990s, could often walk out of prison and leave their gang affiliation behind. But that is increasingly no longer the case, Potok said.

"It used to be quite normal for a member of a racist prison gang to shed his membership at the prison doors as he got out, and that was accepted. More and more that's hard to do. The price for leaving one of these gangs is death," Potok said.

Both the SPLC and the ADL emphasized that there are no known connections between the two gangs.

The ABT is estimated to have up to 3,000 members, almost entirely in state and federal prisons inside Texas, though there are branches in neighboring states. The 211 Crew is estimated to have a few hundred members only in Colorado state prisons.

Cooperation between the two is possible, especially since they traffic the same drugs, but not verified, Potok said.

Speculation of gang cooperation heightened when Clements' killer, Evan Ebel, died in a shootout with Texas cops.

"The most intriguing piece is when Evan Ebel got into a shootout with cops, he was 100 miles from Kaufman County. I know Kaufman County. There's not much there, so it is weird. It is an unusual place for someone to run there," Potok said.

Pitcavage emphasized that there is no evidence linking the murders, and pointed to the fact that Texas authorities are also looking into drug cartels, street gangs, and the possibility of a disgruntled inmate acting alone in the murders. The ADL also passed information to police about the Aryan Circle, a rival gang of the ABT in Texas.

"What does this all mean?" Potok asked. "These cases reflect the fact that prison gangs, which for many years were entirely confined to prisons, are increasingly spilling out onto the streets of our cities and towns around the country."